Residents on Hawaii’s southernmost island already dealt with one tropical storm this year and are coping with the threat of slowly encroaching lava. Now, meteorologists say a potential hurricane is heading toward them and the rest of the island chain.

Here are some questions and answers about the latest storm:

WHEN IS IT EXPECTED TO HIT?

Tropical Storm Ana was forecast to become a hurricane as it moved northwest toward the Hawaiian Islands. The Big Island’s southeastern shores could experience heavy rains and high surf by Friday afternoon. Winds could blow up to 70 mph.

“The Big Island is going to see these effects first,” said Eric Lau, a meteorologist at the National Weather Service in Honolulu. “And then depending on how the system evolves, whether it weakens or maintains itself, parts of the other islands should see very similar effects.”

The current forecast calls for the storm to pass southwest of the Big Island on Saturday before heading south of Oahu on Sunday and Kauai the following day.

WHAT ABOUT EFFORTS TO DEAL WITH THE LAVA?

For several weeks, lava from Kilauea volcano has been inching toward Pahoa, a small historic town in the mostly rural district of Puna, and the main highway connecting the area with the rest of the island. The storm could ground helicopter surveys of the lava that Hawaii County and geologists have been conducting.

Heavy rain and wind also could force workers to suspend the rebuilding Chain of Craters Road, a route partially covered by past lava flows that the county wants to use as an alternate roadway for residents if the latest flow crosses the highway.

Wet weather has kept the lava from starting fires in wooded areas. But the molten rock is being expelled from deep within the Earth and heavy rains would not stop its flow.

WHAT’S HAPPENED SINCE THE LAST STORM?

Power has been restored and downed trees cleared in the Puna district since Tropical Storm Iselle hit in August.

But the land is saturated in the Kau area on the Big Island’s southwestern side after flooding there in recent weeks. The county is preparing for the storm to bring more flooding in this area, said Darryl Oliveira, director of Hawaii County civil defense.

HOW ARE PEOPLE PREPARING?

The governor on Wednesday proclaimed an emergency to help the state respond to the storm. The state Department of Education plans to close Big Island public schools on Friday. Hawaii Volcanoes National Park will also be closed.

Oliveira said residents should store water to help prevent the water shortages that hit areas when Iselle knocked out power in August.

There’s no need to buy containers, he said, if people have receptacles at home they can use to store drinking water. He suggested filling a bathtub with water to flush toilets.

“Those are simple things that the average homeowner could do ahead of time that doesn’t cost much and could put them in a better position for post-impact recovery,” Oliveira said.

Hawaii Emergency Management Agency spokeswoman Shelley Kunishige said the state is encouraging people to review their emergency plans, monitor media and use the hashtag #anahawaii when tweeting.

“We’ve had many quiet years. And this year seems to making up for it,” said Kunishige.

BESIDES STORMS AND VOLCANOS, THE BIG ISLAND HAS EARTHQUAKES. WHY LIVE THERE?

Unlike Honolulu, the state’s biggest city on the island of Oahu, the Big Island still has affordable land and can offer a more rural way of life.

Residents know the risks and take steps to protect themselves. For instance, there are special insurance requirements to buy land in certain lava zones. Many also live off the grid, using solar panels for power and catchment tanks for water supply.

WHEN WAS HAWAII’S LAST HURRICANE?

Iniki slammed into Kauai as a Category 4 hurricane in 1992, killing six people and destroying more than 1,400 homes.

In August, Iselle approached the Big Island as a hurricane, but it weakened to a tropical storm when it made landfall. It still caused damage. State officials postponed voting in a primary election in two badly hit precincts, though balloting was held in the rest of Hawaii as scheduled.